RRB GROUP D Chemistry Quiz - 66

First ionization enthalpy of aluminium is lower than that of magnesium. Which of the following reason is correct?

The wavelength of an electron moving with a velocity of 2.05 × 10⁷ m s^-1 is

Relation between vapour density and molecular weight

The rate of diffusion Ethane is twice that of A. The molecular mass of A is-

Gases neither have definite shape nor definite volume . To liquefy the gases , conditions required are 

Ratio of radius of 2^nd  orbit and 4^th  orbit for hydrogen atom is

Of the three metals X , Y and Z , X reacts with cold water , Y with hot water and Z with steam. Identify X , Y and Z?

Which of the following is the closed system ?

During the transition of electrons from higher energy levels to lower energy levels. Energy is-